Solve the following problem:
Q: Copper tubes 25 mm in diameter and 0.75 m long are used to boil saturated water at 1 atm.
(a) If the tubes are operated at 75% of the critical heat flux, how many tubes are needed to provide a vapor production rate of 750 kg/h? What is the corresponding tube surface temperature?
(b) Compute and plot the tube surface temperature as a function of heat flux for 0.25 < q"s/q"max="">< 0.90.="" on="" the="" same="" graph,="" plot="" the="" corresponding="" number="" of="" tubes="" needed="" to="" provide="" the="" prescribed="" vapor="" production="" rate.="">